You are so incredible, I mean your landscapes are looking so real, just like a photo. Do you have any landscapes photos where you get the ideas from or do you just think about something and paint it? (if someone else already asked this question, I'm terrible sorry ^^") just wanted to say that, because your pictures make me so happy please keep doing your awesome work (sorry for the bad english, it is not my mother tounge ^^")
As for the image - Sometimes I use references. Mostly for texturing. Thinking and watching are the most important things. Every information is out there. Just keep your eyes open when you have a walk. You'll see so much in that time. Try to store the information somewhere (brain, sketchbook, etc.) and developed some ideas of what you have seen.